During recent years there have been repeated reports of extravagant exploitation of the walrus by Eskimos and these have been strengthened by aerial observation of many headless carcasses on beaches of the Bering Sea. So in 1958 the United States Fish and Wildlife Service decided upon an inquiry into the Pacific Walrus, and its hunting and utilization by Eskimo in the Bering Sea region.

For some years past I have had a feeling that our approach to the conservation of the flora and fauna all over the world, but especially in Africa, has been too static. This does not fit in well with the natural situations which we want to perpetuate, for they are nearly all dynamic situations. Admittedly we have moved our standpoint to some extent recently: for instance, the idea that particular species endangered by advancing civilization could survive by giving them individual protection has been generally discarded in favour of conserving the habitats in which such species live and which are prerequisites to their continued existence. But there is still much emphasis on trying to retain the status quo, say in a national park or strict natural reserve, by putting around it a real or symbolic fence and regarding the area and its ecology as sacrosanct and there for ever. And yet wherever a particular ecological situation has been studied, whether it is hinged on elephants or earthworms, the conclusion is always reached that it is dynamic–subject to continual change of balance of populations, of food relations, of chemistry and physics of the environment. Indeed nature will never stand still however much we might sometimes wish it to; and on top of all the natural changes are others imposed by mankind.

It has been realized for a decade that the management of wild animals would be greatly facilitated if a method could be found for their ready capture and handling. The need for such a method has become accentuated in recent years with the increasing interest in wild life, and also with the problems associated with a reduction in the number of wild animals combined with a decrease in the amount of space available for their natural existence. Much work has been done on the catching and marking of animals such as birds, fishes, whales and seals. It is only recently that effective methods are being evolved for the capture of the larger land mammals, such as antelope, for marking and other purposes such as body measurements and weighing, as well as the collecting of samples for pathological or parasitological study. This form of direct control of wild animals is opening up new vistas of wild life management in Africa, and it is thought that the use of these methods may have similar application to wild animals in other regions and parts of the world, both as a means of increasing our knowledge of their habits, ecology and physiology, and in direct management such as capture for transport to other areas, vaccination and occasional therapeutic veterinary interference.

The lake damming the Zambezi river at Kariba will eventually be 175 miles long and 2,000 square miles in extent. Much of the flooded land was rich in wild animals. As the country either side of the Zambezi is not a gentle slope, but very hilly, the animals that lived in the inundated areas were not gradually driven away by an advancing tide line, but on the contrary, found the water advancing on them from every side. They were accustomed to floods and merely sought higher ground, but when that in its turn was inundated or remained above the lake only as an island, the marooned animals—if they were not rescued—would either drown or run out of food and starve.